1. Field of the Invention
The subject invention relates to a thrust bearing assembly as part of an engine assembly for use in a vehicle and a method of aligning a thrust bearing in the engine assembly.
2. Description of the Related Art
Crankshafts are journaled in engine blocks by a series of axially spaced engine bearings. Each engine bearing includes an upper bearing half seated in an arcuate recess of the block and an accompanying lower bearing half clamped tightly against the upper bearing half by a supportive bearing cap bolted to the engine block. At least one of the engine bearings in the set is designed to absorb axial thrust forces imported by the crankshaft during operation. The so-called thrust bearing differs from the other engine bearing in that it has two axially spaced thrust flanges that project radially outwardly. The thrust bearing presents opposite axially outwardly directed thrust faces which are seated on their backsides against support surfaces of the block and engage associated lobes of the crank shaft, when necessary, to provide the thrust support. These thrust flanges typically have a uniform thickness and often are formed with oil grooves and contours to impart a hydrodynamic oil film action to the bearing.
During operation of the engine, loads on the crank shaft tend to force it in axially opposite directions, accounting for the aforementioned thrust loads imparted to the thrust flanges of the thrust bearing. As the thrust loads are applied in one axial direction, it will be appreciated that the forward-most set of upper and lower thrust flanges will be confronted by the crankshaft lobe and will be seated tightly against the associated support surface of the block. It will be further appreciated that when a thrust force is applied by the crankshaft in the axially opposite direction that the opposite set of thrust flanges will be tightly seated against their associated support surfaces of the block. However, this reverse force also has the effect of unseating the forward-most set of thrust flanges. While the unseated thrust flanges will be re-seated the next time the axial thrust forces imported by the crankshaft change, this constant seating and unseating has the detrimental effect of repeatedly bending and thus stressing the thrust bearing of the base of the thrust flanges, which can lead to premature failure of the thrust bearing. Additionally, the repeated seating and unseating can cause the thrust bearing to become misaligned which can also lead to unwanted stress and failure of the thrust bearings.
It is an object of the present invention to minimize or eliminate undesirable seating and unseating of thrust bearings and thus prolongs the operating life of the thrust bearings.